Oil-soluble-dye and process of making the same



concentrated sulphuric acid, fuming Patented Jan. 19, 1932 4 UNITED STATES PATENT; OFFICE.

Hm E. BUG, OF ROSELLE, NEW JERSEY, ASSIGH 'OR 'I'O STANDARD OIL DEVELOPMENT COMPANY, A CORPORATION OF DELAWARE f OIL-SOLUBLE-DYE AND PROCESS .01 THE SAME No Drawing.

This invention relates to a process for iniparting solubility in hydrocarbons and oils generally, to dyestuffs which are normally insoluble therein and to enhancing the solubility in hydrocarbons of dyestuffs which are otherwise sparingly soluble. Dyestuffssolw.

I have found that various dyestuffs insoluble in hydrocarbons, can-be made soluble,

and dyestuffs of limited solubility in hydrocarbons can be made more easily soluble, by causing the same to combine with an oil solu-- ble sulphonic acid, derived from petroleum. The dyestuffs which can be made to react in this manner areorganic and contain a basic group either in combination with an acid or capable of'combining with an acid. The following specific dyestuffs are illustrative of the general class referred to, although this invention is not limited in any way to those specifically mentioned: Victoria green, Bismarck brown, malachite green, methyl violet, nigrosine and methylene blue. The oil-soluble sulphonic acids referred to are those products resulting from the treatment of petroleum and/or petroleum distillates witlh su bphuric acid or sulphuric anhydrid. At the conclusion of such treatment, the residual sulphuric acid, together with organicmat ters, settles out as a sludge andis'. withdrawn. Certain acids are found in the oil phase. These acids are characterized by the presence of sulphur in combination an are predom inantly oil-soluble. For the purposes of this.

' application, they are termed oil-soluble sulphonic acids.

The combination of the dyestuffs with the sulphonic acid may be brought about by contacting the dyestufl with the sulphonic acid, or a salt thereof in an acid medium. I may, for this urpose employ any medium, such as -water, a cohol or hydrocarbon. I may, for

instance, mix the dyestufi to converted with a solution of sulphonic acids in oil as- Application filed Kay 16,

1927. Serial No. 191,929.

obtained by the acid treatment of the petroleum distillate above referred to, or I may extract these sulphonicacids from theoil phase V by the use of solvents therefor, such as a mixture of alcohol and water, and so employ them, or I may --neutralize these sulphonic,

acids either before or after extraction .-,with

any suitable base, and employ either the alcohol-Water solution thereof, or evaporateofi' the solvent and utilize the. salt of-the s'ul v phonic acid so obtained. 7

My preferred method-of operation, .how-

ever, consists in reacting the dyestufi'to. be

converted and the sulphonic acid or .salt' 16 phonlc acid 1s preferably employed in 'the- Y thereof in an aqueous medium. The sul-' form of its alkali metal salt. If-thc dye is employed in the form of its uncom-bined base,

the system should be in acid condition and if a salt of the sulphonic acid is employed as distinguished from the sulphonic acid per se,

I add to the system a quantity of acid, either organic or inorganic suflicient to liberate the sulfonic acid. It will, of course be underformed. i

' The dyestuff so made is ordinarily separated from the solution and dried. If fur-. therpurificationvis desired, it maybe dissolved in organic solvents of low boiling point:

The exact amount of mineral such as, for instance, benzol, chloroform, 81-

cohol, etc.,and the solvent subsequently removedby evaporation. It will be understood oil-soluble dyestuffs by causing dyestufl's of. 1

the class hereinbefore mentioned to combine with an oil-soluble sulphonic acid formed by the treatment of petroleum or with sulphuric acid.

What I claim is:

1. The method of rendering dyestuffs soluble in hydrocarbons, which comprises causing an organic dyestuif containing a basic group to react with an oil-soluble sulphonic acid derived from the treatment of a petroleum oil with sulphuric acid.

2. The method of making oil-soluble dyestufis, which comprises causing an organic dyestufl containing a basic group to react with an oil-soluble sulphonic acid derived from the treatment of a petroleum oil with fumiing sulphuric acid or sulphuric anhydri 3. The method, according to claim 2, in which reaction takes place in an aqueous medium.

4. The method of rendering dyestuffs soluble in hydrocarbons, which comprises causing an organic dyestufi containing a basic group to combine in an acid medlum with oil-soluble sulphonic acid derived fromthe trestment of a petroleum oil with sulphuric am its distillates 5. An oil-soluble product comprising an organic dyestuff, normally substantially in soluble in'oils, in combination with an oilsoluble sulphonic acid derived from petroleum v 6. The method according to claim 2 in which the reaction takes place in an aqueous acid medium.

7. The method according to claim 2 in which the'reaction is carried out in an aque ous medium in the presence of free acid and an alkali metal salt of the 'sulfonic acid whereby the sulfonic acid is obtained by action of said free acid upon said alkali metal salt.

HYYM E. BUG. 

